Telephone system



Dec. 26,1933 7 E, EL U 1,941,232

TELEPHONE SYSTEM Filed April 18, 1933 FIG.

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lNVENTOR E .SP/ELAUER AT TORNEV Patented Dec. 26, 1933 1 TELEPHONE SYSTEM Engelbert Spielauer, Vienna, Austria, assignor to Western Electric Company, Incorporated, New

York, N. Y., 'a corporation of New York Application April 18, 1933, Serial No. 666,637, and in Austria June 16, 1932 9 Claims. (Cl, 179"16 This invention relates to automatic telephone systems and more particularly to systems in which the various switches are'directively responsive to impulses of current. The object of the invention 1 is to provide an eificient and reliable circuit arrangement for. directively controlling automatic switches. I V

It is well known in dial telephone systems that "the transmission of dial impulse's over longtrunks ""10 or through one or more repeaters causes distortion which may result in faulty operation of the directively controlled switches used in establishing telephone: connections. In the case of multiple repeating, the first impulse'of a'series is shortened ll as-well as distorted so that thisimpulse becomes ineffective to operate the selecting mechanism'although Y succeeding impulses are of sufficient length. To correct for distortionit is'well known to provide circuit arrangements-for correcting all of the impulses; to be fully effective such arrangements are somewhat complicated whereas-a more simple arrangement is suitable where only the first impulse of a series is too short to effect the proper response. This invention is an impulse receiving circuit so arrangedthat the associated selector switch will respondtoa very short initial impulse, a part'of the second impulse of the 'incoming train being used for completing the operation of the switch in-response to the first impulse.

, Tothisendthe arrangement 'comprises a primary impulse relay, the usual release relay and an auxiliary impulse relay, the primary'impulse relayire- 'maining deenergized after its release in response to thefirst impulse until-the selector magnet is fully 135 operated-even-though the opening of the impulse circuit is of a shorter duration. A feature of the inventionisan auxiliary impulse relay connected to the impulse'circuit after receipt of theinitial impulse for operating uponclosureof the impulse 34f) circuit during the time the switch is responding to-the first impulse.

The drawing, which forms'a part of thisspecification, illustrates schematically, a portion of a,

selecting mechanism arranged in accordance with the features of this invention. Referring tothej;

vRelay 11 is reoperated bythe energization of its drawingrv "Fig. 1 showsin diagrammatic form a series of impulses; e

- Fig. 2 represents schematically an impulse re sponsive-selecting mechanism.p e

The impulse series illustrated in Fig. 1V is one in which the first impulse is too short to; effect-a proper selective operation while the succeeding impulses are somewhat longer than is required for 5i effecting the proper selective operations; The

circuit from battery through resistance, 14 front contact. of relay 10, back contact of relay13, and throughtheright winding of relay 11 to ground; Relay 11 operates due to the energization of its right winding and closes a circuit for operating the slow to-release relay 13. Relay 13 opens the operating circuit through the right winding of relay 11 but relay 11 is held operated by the circuit from battery through resistance 14, front contact of relay 10, left front contact of relayll, and through both windings ofrelay '11 in series, to ground. No further action takes place until a series of impulsesis received by relay 10. The release of relay 10in response to the first impulse closes a circuit from battery through ,thewin'ding of selector magnet 16, right front contact of relay 13, to ground at the right back contact of, relay 11., The magnet 16 is thus energized in response to the first impulse. Relay, 11 can not reoperate before magnet 16 has fully operated and performed the desired. selecting operation in response to-the first impulse because its initial operating circuit is open at the outer left contacts of relay 13, the latter relay remaining operated during the temporary release of relay 11 in response to incoming impulses.

When relay 10 reoperates, at the end of the. first impulse, a circuitis closed from battery through resistance 14, front contact of relay 10, theleft back contact of relay ll', left frontcontact of relay 13, and through the'left winding of relay 12 to ground. Relay 12 is thereby operated closing a circuit from battery through its right winding and front contact, front contact of magnet, 16, through theright winding v of relay 11 to ground. 100

11 in series, to ground. Relay 11 is thus held operated as long as either of relays 10 and 12 remains operated. Relay 12 remains operated by the circuit through its right Winding until magnet 16 releases. When magnet 16 releases, relay 12 releases, relay 11 being held by relay 10 if this relay has not again released in response to a second incoming impulse. When relay 10 re leases, (or when relay 12 releases, if relay 10 has already received the second impulse before magnet 16 and relay 12 release), relay 11 releases causing the above cycle of operations, as described as occurring in response to the receipt of the first impulse, to be repeated.

Although the relay 10 has been described as be ing responsive to incoming impulses, the front contacts of this relay mayals'o be considered as representing the interrupter contacts of an impulse sender such as a dial. whether these contacts are directly or indirectly responsive to the operation of an impulse sender, the arrangement of relays 11, 12 and 13 is effective to insure the proper operation of the selecting mechanism represented by magnet 16, the circuit for magnet 16 being closed until its armature: is fully attracted and opened until the armature has been released irrespective of the length of the impulse received.

Although disclosed in an arrangement for directly controlling an'impulse responsive selecting mechanism, the invention is also applicable to impulse repeaters generally. For use as a repeater, the magnet 16 of Fig. 2 becomes an impulse repeating relay, an additional set of normally closedcontacts being connected by an additional front contact of the slow-'to-release relay 13 across the conductors over which the impulses are to be repeated.

What is claimed is:

1. In combination, a magnet, an impulse receiving circuit, a first relay energized over said circuit,

an auxiliary relay, means effective upon the release of said first relay in response to the opening of said. circuit for energizing said magnet, means effective upon the release of said first relay for disconnecting said first relay from said circuit and for connecting said auxiliary relay to said-circuit, and means renderedeffective by the operation of said auxiliary relay over said circuit and the complete operation of said magnet for reoperating said first relay.

2. In an impulse receiver, a first relay responsive to incoming impulses, a magnet for operation in accordance with incoming impulses, a second relay operated in response to the operation of said first relay, the operating circuit for said magnet being closed by the release and opened by the operation of said second relay,a thirdrelay, an operating circuit for said third relay closed by the release of said second relay, and a circuit for holding said third relay and reoperating said second relay, said last mentioned circuit being closed by the operation and opene by the release of said magnet. 1

3. In an impulse receiver, a first relay respon-. sive to incoming impulses, a magnet for operation in accordance with incoming impulses,a second relay operated in response to the operation of said first relay, the operating circuit for said magnet being closed by the release and opened by the operation of said second relay, a third relay, an operating circuit for said third relay closed by the release of said second relay, a circuitfor holding said third relay and reoperating said second "e relay independently of said first relay, and a cir- Irrespective of r cuit for holding said second relay after its reoperation independently of said first relay, said last mentioned circuit being opened in response to the release of said magnet.

4. In combination, an impulse receiving relay, a magnet for operation in accordance with impulses received by said relay, a second relay initially operated in response to the operation of 'said impulse receiving relay, the operating circuit for said magnet being closed by each release and opened by the succeeding reoperation of said second relay, a third relay, the operating circuit for said third relay being under the joint control of said first and second relays, and a circuit for holding said third relay and reoperating said second relay, said last mentioned circuit being under the sole control of said magnet.

5. In combination, an impulse receiving relay, a magnet for operation in accordance With impulses received by said relay, and means for correcting said impulses to insure the properresponse of said magnet, said means comprising a first relay for opening and closing the operating circuit of said magnet, the initial'operation and release of said first relay being controlled'by said impulse receiving relay, anda second relay for controlling the reoperation of said first relay, the operating circuit for said second relay being dependent upon the complete operation of said magnet and the reoperation of said impulse receiving relay. r Y

6. In combination, an impulse receiving relay, a magnet for operation in accordance with impulses receivedby said relay, a first auxiliary relay for closing and opening the operatingcircuit for said magnet, a second auxiliary relay, and circuit connections such that the initial operation and release of said impulse receiving relay efiects the initial operation and release of said first auxiliary relay, each succeeding operation of said impulse receiving relay eifects the operation of said second auxiliary relay without effecting the operation of said first auxiliary relay, the operation of said second auxiliary relay effacts the reoperation of said first auxiliary relay, and each succeeding release of said impulse receiving relay effects the release of said first auxiliary relay. I

'7. In combination, an impulse receiving relay, a first auxiliary relay, a' second auxiliary relay,

the operation of said first auxiliary relay being effected by the initial operation of said impulse receiving relay, and the initial-release of said first auxiliary relay being effected bythe' release of said impulse receiving relay upon receipt of the first impulse of a series, a magnet for operation in accordance with impulses received by said impulse receiving relay, a circuit closed by the release of said first auxiliary relay for operating said magnet, a circuit closed by the release of said first auxiliary relay and the reoperation of said impulse receiving relay after the first impulse for operating said second auxiliary relay, means including said second auxiliary relay for preventing the reoperation of said first auxiliary relay until said magnet has operated in response to the first impulse, and means for preventing the second release of said first auxiliary relay until said magnet has released.

8. In combination, an impulse receiving relay, a first auxiliary relay, a second auxiliary relay, the operation-of said first auxiliary relay being effected by the initial operation of said impulse receiving relay, and the initial release of said first auxiliaryrelay being effected by the release of i .said impulse receiving relay upon receipt of the first impulse of a series, a magnet for operation in accordance with impulses receivedby said impulse receiving relay, lease of said first auxiliary relay for operating Said magnet, a circuit closed by the release of said first auxiliary relay and the reoperation of said impulse receiving relay "after the first impulse for operating said second auxiliary relay, means including said second auxiliary relay for preventing the reoperation of said first auxiliary relay until said magnet has operated in response to the first impulse, and means for holding said first auxiliary relay after its reoperation until said magnet has released.

9. In combination, a first relay, a circuit for operating said first relay, cluded in said circuit, means for alternately opening and closing said impulse contacts, a slow-toa circuit closed by the re-' impulse contacts in-' auxiliary relay, an operating circuit for said auxiliary relay closed by the operation of said slowto-release relay and release of said first relay, said operating circuit including said impulse contacts, a circuit closed by the operation of said magnet for holding said auxiliary relay and for reoperating said first relay, and a circuit controlled exclusively by said auxiliary relay for holding said first relay after its reoperation.

ENGELBERT SPIELAUER. 

